skill-ef-core-8-expert

name	Skill: EF Core 8 Expert
description	Use when working with EF Core 8, repositories, transactions, query optimization, and migrations.

Skill: EF Core 8 Expert

Purpose

Use this skill when working with Entity Framework Core 8, SQL Server, repositories, transactions, and query optimization.

Querying

Prefer:

• AsNoTracking() for read-only queries.
• Explicit Include calls.
• Projection to DTOs when only partial data is required.
• AsSplitQuery() for large include graphs.

Avoid:

• Lazy loading.
• N+1 query patterns.
• Loading entire tables into memory.
• Client-side evaluation.

Updates

• Use SaveChangesAsync(cancellationToken).
• Wrap write operations in explicit transactions when multiple operations must succeed together.
• Use savepoints for retryable concurrency or uniqueness scenarios.

Transactions

Prefer:

await using var transaction =
    await dbContext.Database.BeginTransactionAsync(cancellationToken);

Never:

• Use synchronous transaction APIs.
• Ignore transaction failures.

Performance

• Evaluate generated SQL.
• Use compiled queries only for proven hotspots.
• Push filtering and aggregation to the database.
• Avoid client-side evaluation.

Modeling

• Configure relationships explicitly.
• Use Fluent API for complex mappings.
• Avoid magic strings.
• Keep entities persistence-focused.

Concurrency

• Handle concurrency conflicts explicitly.
• Use optimistic concurrency where appropriate.
• Never silently overwrite concurrent changes.

Migrations

• Generate deterministic migrations.
• Review migrations before committing.
• Avoid destructive changes unless explicitly requested.

Testing

• Prefer integration tests against a real database.
• Do not rely exclusively on the InMemory provider.
• Verify generated SQL when query behavior is critical.